ABSTRACT This proposal is in response toNIDCR Behavioral or Social Intervention Clinical Trial Planning Grant (R34), PAR-14-342. Data from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) indicate that approximately 56% of American children aged 6-8 years have dental caries and these rates are higher among Texas children as compared to the national average.Oral diseases are progressive and can ultimately lead to pain and tooth loss, severe conditions that affect quality of life. In 2013, the Texas 83rd legislative session added ?oral health? as a required topic to the state education code governing coordinated school health programs. Unfortunately, although primary school oral health education interventions exist, none have been rigorously evaluated and documented as clinically efficacious in reducing incidence of dental caries among children. At school, health promotion messages can be integrated into the school curricula and activities. Inclusion of good oral health education habits including tooth brushing, flossing and a healthy diet ensures that these messages are reinforced among children, enabling them to develop healthy, lifelong oral health habits. CATCH (Coordinated Approach to Child Health), a Texas Education Agency-approved coordinated school health program, is an evidence-based health education program that has demonstrated long term effectiveness in improving diet and physical activity behaviors, and reducing obesity among diverse populations. The CATCH team recognizes the need nationwide and in Texas to integrate oral health into the curriculum and activities and evaluate its efficacy in reducing caries outcomes. In this proposal, we will augment the current CATCH K-2 curriculum development of oral health education intervention materials called CATCH Healthy Smiles. We will also conduct a small-scale feasibility testing of the intervention materials, measures, methods, and training approaches. Finally, we will develop the clinical protocol to guide a subsequent group-RCT powered for change in incidence of dental caries. The specific aims of this proposal are: through the Aim 1. To develop CATCH Healthy Smiles, a new school-based oral health education intervention augmenting the existing K-2 grade CATCH program, and related training procedures for school staff, and research protocols needed to plan a RCT to evaluate program efficacy in improving child oral health as measured by dental caries incidence as the main outcome. Aim 2. To conduct a small scale feasibility study of the CATCH Healthy Smiles program using a mixed-methods one-group pre-post evaluation design within two elementary schools (n=90 parent-child dyads; 15 dyads per grade per school), with the involvement of school teachers, staff, and parents of children attending grades K-2 serving primarily low-income children in Houston, Texas. Results will inform a subsequent large-scale school-based group-RCT to evaluate intervention efficacy in reducing incidence of caries lesions.